JP2002294162A - Process for producing coating material resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for producing a coating material resin composition, which is suitable for improving the dispersion of pigments and improving the productivity. SOLUTION: This process for producing a coating material resin composition comprises mixing two or more pigments for forming the composition, dispersing the pigment mixture in a blend of a resin and a solvent at an optimum dispersion blend ratio predetermined by the Daniel pour point method (flow point method), and adding ingredients required for giving a prescribed coating material resin composition to the dispersion. It is desirable that the coating resin material composition comprises an electrodeposition coating material composition in particular.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a resin composition for paints, and more particularly to a method for producing a resin composition for paints suitable for improving dispersibility of a pigment and improving productivity.

[0002]

2. Description of the Related Art Conventionally, coating resin compositions usually contain specific coloring materials such as inorganic pigments and organic pigments, although they vary depending on the use. When the pigment is dispersed in the coating resin composition, if the dispersibility of the pigment is low, a good coating film cannot be obtained and various troubles tend to occur at the time of coating, and the quality of the coating is deteriorated. There are cases. Particularly, in the case of an electrodeposition paint, if the dispersibility of the pigment is low, the pigment in the resin composition for a paint tends to settle. In order to suppress the sedimentation, the electrodeposition tank is provided with a stirring device to supply a liquid flow to the electrodeposition paint. At the time of electrodeposition coating, a part of the pigment which settles down is deposited on the horizontal portion of the object to be coated, and causes a deterioration in the appearance of the coating. For example, in the case of an automobile body or an outdoor unit of an air conditioner, a pigment may be deposited on a horizontal surface of an object to be coated facing upward in the electrodeposition tank, and uniformity, smoothness, and sharpness of the coating film are problematic. It is easy to be.

[0003] In order to improve the dispersibility of the pigment in the resin composition for coating, there is a method of changing the composition of the resin composition for coating, for example, a method of changing the resin for dispersion.
However, changing the composition of the coating resin composition itself requires a new confirmation of the properties of the coating resin composition over a long period of time.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to improve the dispersibility of pigments without changing the composition of the resin composition for coatings, thereby improving the productivity and the properties of the coating film. It is an object of the present invention to provide a method for producing a resin composition for coatings that can be performed.

[0005]

The object of the present invention described above is achieved by the following invention. That is, the method for producing a resin composition for coating of the present invention comprises: <1> an optimal dispersion mixing ratio of a plurality of pigments constituting the resin composition for coating with a resin and a solvent which have been determined in advance by the Daniel pour point method. And then adding a component for forming a predetermined resin composition for a coating, the method comprising the steps of: <2> The method for producing a coating resin composition according to <1>, wherein the coating resin composition is an electrodeposition coating composition.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below. According to the present invention, a plurality of pigments constituting a coating resin composition are mixed, and the pigment of the mixed system is optimally dispersed with a resin and a solvent which are determined in advance by a Daniel pour point method (also referred to as a flow point method). It is characterized in that the components are dispersed in a compounding ratio, and thereafter, a component for forming a predetermined resin composition for a paint is added. In the present invention,
The target resin composition for coating is not particularly limited, and can be suitably used for an electrodeposition coating composition. Coloring pigments, extender pigments, rust-preventive pigments, and the like are generally blended in the coating resin composition, and the pigments constituting the coating resin composition are mixed. The mixing is performed by applying the optimum dispersion mixing ratio of the resin and the solvent determined by the point method.

[0007] The Daniel pour point method is described, for example, in "Paint Flow and Pigment Dispersion (TC Patton).
Authors, 1971 ". This method first
Several kinds of mixed solutions (referred to as vehicles) in which the ratio between the solvent amount and the resin amount is changed. Then, while adding one type of vehicle into a 100 ml beaker containing a specific amount of pigment, the mixture is stirred with a glass rod, and the amount of the vehicle when it reaches the “flow point” is measured. Similarly, the same measurement is performed using another vehicle having a different solvent / resin ratio. Using the results thus obtained, a flow point curve is drawn with the horizontal axis representing the resin solid content in the vehicle and the vertical axis representing the amount of vehicle required to reach the flow point. The flow point curve is a U-shape having a minimum value, and the composition at this minimum value is a composition that can balance the resin, the solvent, and the pigment and can perform dispersion most efficiently.

The determination of the pour point requires some experience, but is generally as follows. That is, when kneading the pigment while adding the vehicle to the beaker as described above,
The contents are initially paste-like, but as you add more vehicle, you will not feel much resistance to stirring.
At this time, if the glass stick is pulled straight up onto the beaker, the droplets attached to the glass stick remain in a thin film form, and the last few drops fall at intervals of 1 or 2 seconds. , That is the pour point.

The Daniel pour point method described in the above-mentioned document is a method for obtaining an optimum composition for a mill base using one kind of pigment (TiO _{2 in the} document). In addition, when two or more pigments are contained, it is also described that the amount of the vehicle at the time when the flow point of each pigment is reached is obtained, and the optimum composition is obtained from a proportional calculation according to the pigment composition ratio. I have. However, the method for producing a coating resin composition of the present invention is a coating resin composition containing at least two or more pigments, and a mixture of two or more pigments is determined in advance by the Daniel pour point method. Apply and mix the optimal dispersion and mixing ratio with the resin and solvent previously set.

The resin composition for paints obtained by the production method of the present invention can reduce the particle size of pigment particles to a predetermined value in a shorter time than obtaining the optimum dispersion mixing ratio of resin and solvent for each pigment. (For example, 5 μm),
The dispersibility of the pigment can be improved.

Particularly, in the case of electrodeposition coating, the horizontal appearance tends to be inferior to the vertical appearance. The reason for this is that the electrodeposition paint uses water having a specific gravity of 1 as a solvent, and the viscosity of the resin composition for the paint is low, which is close to that of water. On the other hand, a pigment having a high specific gravity is contained in the paint composition. Because it is. In an electrodeposition paint that forms a film after (or while immersing) the object to be coated in the electrodeposition paint, the electrodeposition is performed under a gentle stirring state, and as a result, the object to be coated (for example, an automobile body) is formed. A phenomenon in which the pigment falls on the horizontal portion and accumulates easily occurs. Generally, when the pigment accumulates, so-called bumpy protrusions tend to be formed at the portion, and abnormal deposits are observed as so-called bumps during baking.

According to the method for producing a resin composition for a coating composition of the present invention, the degree of dispersion of the pigment can be improved in a short period of time. , The sedimentation speed of the pigment can be suppressed, and the occurrence of the above-mentioned bumps can be prevented.

In the present invention, when a resin composition for a paint is produced, it has at least a “dispersion step” and a “dissolution step”. In the “dispersion step”, a plurality of pigments constituting the coating resin composition are mixed, and the mixed pigment is mixed with D
Disperse at the optimum dispersion compounding ratio with the resin and solvent determined by the aniel pour point method. In this case, the pigment to be mixed is a coloring pigment; for example, titanium white, carbon black, red iron oxide, extender; for example, kaolin, talc, calcium carbonate, clay, silica, rust-preventive pigment; for example, a chromium pigment (strontium) Chromate, zinc chromate), lead pigments (basic lead silicate, basic lead chromate, lead tin, cyanamide lead), phosphoric acid pigments (aluminum phosphate, zinc phosphate, calcium phosphate), molybdic acid pigments (phosphorous Not only aluminum molybdate, zinc phosphomolybdate, etc.), boric acid pigments (barium metaborate, etc.) and cerium pigments (cerium carbonate, cerium acetate, cerium pyrophosphate, etc.) An embodiment in which at least two or more kinds are mixed is also included.

As the pigment dispersing resin, in the case of an electrodeposition paint, a general resin for a cationic electrodeposition paint (epoxy sulfonium salt type resin, epoxy quaternary ammonium salt type resin, epoxy type tertiary amine type resin) And acryl-based quaternary ammonium salt-type resins) can be used.

The solvent varies depending on the type of the pigment dispersing resin, but one or more solvents can be arbitrarily selected. Specifically, water is mainly used as the solvent, but water containing a small amount of an organic solvent such as butyl cellosolve and dipropylene glycol monobutyl ether can also be used.

In the [dispersion step], a wetting agent, a surfactant, an antifoaming agent and the like can be added to the obtained pigment-dispersed paste in addition to the pigment, the pigment-dispersing resin and the resin, if necessary. As the surfactant or the wetting agent, an alkyl imidazoline, an acetylene-based alcohol, or the like is used. A plasticizer may be added to the pigment paste. Examples of the plasticizer include a high-boiling water-miscible material such as nonylphenol or ethylene oxide adduct of bisphenol A or propylene oxide adduct.

In the "dissolving step", other components are further added. Here, the other components are arbitrarily selected depending on the use of the resin composition for a coating. For example, in the case of an electrodeposition coating, there are a resin for dispersing a pigment, a solvent, and other components.

Examples of the base resin include a hydrophilic film-forming resin having a cationic group. This resin is derived from a bisphenol type epoxy resin and has a number average molecular weight of 100 to 10,000, preferably 1,000 to 10,000.
3000 things are available. The base equivalent of the base resin is
It may be in a normal range, specifically, 40 to 150 (meq / 100 g), preferably 60 to 100 (meq / 100 g).
100 g). Specific examples include a bisurethane compound reacted with a diisocyanate compound or a heterourethane compound reacted with another active hydrogen compound and an epoxy resin as disclosed in Japanese Patent Application Laid-Open No. 5-306327 proposed by the present applicant. And an oxazolidone ring-modified epoxy resin obtained by subjecting the compound to a dealcoholation reaction.

As a curing agent, a block polyisocyanate compound is used. The blocked isocyanate curing agent can be obtained by an addition reaction between a polyfunctional isocyanate compound and an isocyanate blocking agent. As the polyfunctional isocyanate compound to be used, an aliphatic, alicyclic or aromatic polyisocyanate is used. For example, tolylene diisocyanate, xylylene diisocyanate, 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate and its isocyanurate. On the other hand, isocyanate blocking agents are those in which a blocked isocyanate compound generated by addition is stable at room temperature, and can dissociate blocks when heated to 100 to 200 ° C. to regenerate free isocyanate groups. desirable. For example, lactam compounds (e-caprolactam, γ-butyrolactam, etc.), phenol compounds (phenol, cresol,
Xylenol), alcohol compounds (such as methanol, ethanol, furfuryl alcohol, and butyrosolve), and oxime compounds (such as methyl ethyl ketone oxime and cyclohexanone oxime).

As a curing catalyst, a tin compound (dibutyltin oxide, dibutyltin dilaurate, etc.) can be used.

The amount of the blocked isocyanate curing agent to be added is preferably determined by the ratio to the base resin. Usually, the mass ratio between the base resin and the curing agent is 9
It is set to 0/10 to 50/50. When the ratio of the curing agent is small, sufficient curability cannot be obtained, and when it is too large, the heating loss may increase.

The resin emulsion is prepared by mixing a base resin and a curing agent with a water-soluble organic acid such as formic acid, acetic acid, propionic acid, lactic acid, citric acid, malic acid, tartaric acid and acrylic acid or an inorganic acid such as hydrochloric acid and phosphoric acid. It is obtained by dispersing in an aqueous medium containing a wetting agent.

The cathodic electrodeposition coating composition of the present invention can be applied to a desired substrate surface by cationic electrodeposition. The cationic electrodeposition coating itself is performed according to a known method, and generally has a solid content of 5 to 40% by mass, preferably 15% by mass.
An electrodeposition bath comprising the cathodic electrodeposition coating composition of the present invention, diluted with deionized water so as to have a pH of from 5.5 to 8.5% and usually adjusted to a bath temperature of not more than 25% by mass. 20 ° C-3
The temperature can be adjusted to 5 ° C. and the load voltage can be adjusted to 100 to 450 V.

The thickness of the electrodeposition coating that can be formed using the cathodic electrodeposition coating composition of the present invention is not particularly limited, but is generally 5 to 60 μm, preferably 5 to 60 μm, based on the cured coating film. Is suitably in the range of 10 to 40 μm. The baking curing temperature of the coating film is generally 100 to 200.
It is suitable to bake at a temperature of 150 ° C., preferably 150 to 180 ° C. for a time of 10 to 30 minutes.

[0025]

Hereinafter, embodiments of the present invention will be described.
The present invention is not limited to this embodiment. (Example 1) (Synthesis of oxazolidone ring-containing base resin) A flask equipped with a stirrer, a cooler, a nitrogen injection tube, a thermometer and a dropping funnel was prepared. 2,4- / 2,6
-Tolylene diisocyanate (mass ratio = 8/2) 92
g, 95 g of methyl isobutyl ketone and 0.5 g of dibutyltin dilaurate, and 21 g of methanol was further added dropwise with stirring. The reaction starts at room temperature,
According to the invention, the temperature was raised to 60 ° C. Thereafter, after the reaction was continued for 30 minutes, 57 g of ethylene glycol mono-2-ethylhexyl ether was added dropwise from a dropping funnel, and 42 g of a bisphenol A-propylene oxide 5 mol adduct was further added. The reaction was performed mainly in the range of 60 ° C. to 65 ° C., and was continued until the isocyanate group disappeared while measuring the IR spectrum. Next, 365 g of an epoxy resin having an epoxy equivalent of 188 synthesized from bisphenol A and epichlorohydrin was added, and the temperature was raised to 125 ° C. Thereafter, 1.0 g of benzyldimethylamine was added and reacted at 130 ° C. until the epoxy equivalent reached 410. Subsequently, when 87 g of bisphenol A was added to the reaction vessel and reacted at 120 ° C., the epoxy equivalent became 1190.
After cooling, 11 g of diethanolamine, 24 g of N-methylethanolamine, and 25 g of a ketiminated product of aminoethylethanolamine (79 mass% solution in methyl isobutyl ketone) were added, and the mixture was reacted at 110 ° C. for 2 hours. Then, the non-volatile content is 80% with methyl isobutyl ketone.
To obtain an oxazolidone ring-containing base resin.

(Synthesis of Blocked Isocyanate) A flask equipped with a stirrer, a condenser, a nitrogen injection tube, a thermometer and a dropping funnel was prepared. To this flask were added 199 g of a trimer of hexamethylene diisocyanate (Coronate HX: manufactured by Nippon Polyurethane Co., Ltd.) and 11.3 g of ε-caprolactam. Then, the contents in the flask were heated to 80 ° C. and uniformly dissolved. Here, 32 g of methyl isobutyl ketone, 0.05 g of dibutyltin dilaurate and 1,8-diazabicyclo (5,
0.05 g of (4,0) -7-undecene was added. While stirring the mixture while bubbling nitrogen through it, 78.3 g of methyl ethyl ketoxime was added dropwise from the dropping funnel over 1 hour while paying attention to heat generation. The reaction was continued until the isocyanate group disappeared in the IR spectrum to obtain a blocked isocyanate crosslinking agent. 350 g (solid content) of the base resin and 150 g (solid content) of the crosslinking agent were mixed, and ethylene glycol mono-2-ethylhexyl ether was added so as to be 3% (15 g) based on the solid content.
Then, glacial acetic acid was added to neutralize the mixture to a neutralization ratio of 40.5%, and the mixture was diluted slowly with ion-exchanged water. Then, methyl isobutyl ketone was added under reduced pressure to a solid content of 36.0%. Was removed to obtain a resin emulsion.

(Production of Pigment Dispersion Resin) Stirrer, cooler,
A flask equipped with a nitrogen injection tube, a thermometer and a dropping funnel was prepared. 222.0 g of isophorone diisocyanate was added to the flask, and methyl isobutyl ketone 3 was added.
After diluting with 9.1 g dibutyltin dilaurate 0.1.
2 g were added. After the temperature was raised to 50 ° C., 131.5 g of 2-ethylhexanol was dropped from the dropping funnel over 2 hours while stirring while bubbling nitrogen through. By appropriately cooling, the reaction temperature was maintained at 50 ° C during this time. As a result, 2-ethylhexanol half-blocked isophorone diisocyanate was obtained. (Solid content 90
%)

Another flask equipped with a stirrer, condenser, nitrogen injection tube, thermometer and dropping funnel was prepared. 376.0 g of Epon 828 (epoxy resin manufactured by Shell Chemical Co., Ltd.) and 114.0 g of bisphenol A were added to this flask, heated to 130 ° C. under a nitrogen atmosphere, 0.75 g of dimethylbenzylamine was added, and an exothermic reaction was performed at 170 ° C. for 1 hour. By the reaction, a bisphenol A type epoxy resin having an epoxy equivalent of 490 was obtained. Then, 14
After cooling to 0 ° C., 198.4 g of the above-mentioned 2-ethylhexanol half-blocked isophorone diisocyanate was added, and the mixture was allowed to react at 140 ° C. for 1 hour. Then, 161.8 g of ethylene glycol monobutyl ether was added, and the reaction mixture was cooled to 100 ° C. did. Add thiodiethanol 3
66.0 g, dimethylolpropionic acid 134.0 g,
And 144.0 g of deionized water.
Until an acid number of 0.241 is obtained, and then
Dilution with 353.3 of ethylene glycol monobutyl ether gave a pigment-dispersed resin having a sulfonium conversion of 82%.
(Solid content 50%)

(Measurement by the Daniel pour point method) The pigment dispersion resin, deionized water as a solvent, carbon black, kaolin, and titanium dioxide (mass ratio of each pigment = 1.
3: 53.0: 45.7) and the Daniel pour point method is measured using a pigment mix char. First,
By diluting with deionized water, six types of mixed liquids having a pigment dispersion resin solid content of 3, 5, 10, 15, 20, and 25% by mass were prepared. Next, each mixed solution was added with stirring with a glass rod into six beakers each containing 20 g of the above pigment mix char, and a pour point was searched for. Then, using the obtained six kinds of pour points, a resin mass-a vehicle mass curve required to reach the pour point was drawn, and the minimum value of this curve,
That is, the optimum mixing ratio (in the present embodiment, solvent such as deionized water: pigment dispersion resin solids: pigment mix char = 57.8: 10.2: 100 (mass ratio),
Deionized water: Pigment dispersion resin: Pigment mix char = 4
7.6: 20.4: 100 (mass ratio) was found.

(Dispersion Step of Pigment Dispersion Paste) Using the above optimum mixing ratio, 204 g of pigment dispersion resin, 476 g of deionized water, and 1000 g of pigment mix char were charged into a sand grind mill and dispersed at a temperature of 45 ° C. for 20 minutes. As a result, a pigment-dispersed paste having a particle size of 5 μm was obtained. The particle size was measured using a grind gauge. Next, 296 g of the pigment-dispersed resin and 475 g of deionized water were added to obtain a solid content of 51% by mass.
A final pigment-dispersed paste in a weight ratio was obtained.

(Preparation of Electrodeposition Coating) 381.9 parts by mass of resin emulsion prepared above and pigment dispersion paste 1
495.6 parts by mass of ion-exchanged water was mixed with 22.5 parts by mass to prepare a cationic electrodeposition coating composition having a solid content of 20.0% by mass. The solid content ratio between the total pigment content and the total resin content in the cationic electrodeposition coating composition was 1/3 mass ratio.

Comparative Example 1 500 g of the pigment dispersion resin
And 951 g of deionized water as a solvent, carbon black, kaolin, and titanium dioxide (mass ratio of each pigment = 1.
3: 53.0: 45.7) was charged into a sand grind mill without using the Daniel pour point method, dispersed at a temperature of 45 ° C. for 20 minutes, and pulverized to a particle size of 10 μm. (Solid content: 51% by mass, pigment mix char: pigment dispersion resin solid content = 1: 0.25 mass ratio) A final pigment dispersion paste was obtained. (Preparation of electrodeposition paint) The same procedure as in Example 1 was carried out.

(Comparative Example 2) (Measurement by Daniel pour point method)
The Daniel pour point method is measured using deionized water as a solvent and carbon black. First, the pigment dispersion resin solid content is reduced to 3,5,1 by dilution with deionized water.
Six types of mixed liquids were prepared so as to be 0, 15, 20, and 25% by mass. 20 g of carbon black each 6
Each mixed solution was added to each beaker while stirring with a glass rod, and a pour point was searched for. Using the obtained six types of pour points, a vehicle mass curve required to reach the resin solid content-pour point was drawn, and the minimum value of this curve, that is, the optimum blending ratio (in this comparative example, deionized water Solvent: resin solids: carbon black = 195.4: 21.8: 1
00 (mass ratio) was found. Hereinafter, for kaolin and titanium dioxide, respectively, a solvent such as deionized water and the like: resin solid content: kaolin = 67.6: 1 in the same manner as described above.
Solvents such as 1.9: 100 (mass ratio), deionized water, etc .: resin solid content: titanium dioxide = 39.4: 2.1: 100 (mass ratio).

(Dispersion process of pigment dispersion paste) 151 g of pigment dispersion resin, 488 g of deionized water, and 151 g of pigment dispersion resin obtained by proportionally distributing the optimum mixing ratio individually determined for each of the above pigments as the composition of the pigment mix char. Charge 1000g of pigment mix char into a sand grind mill, temperature 4
The dispersion was performed at 5 ° C. for 20 minutes to obtain a pigment dispersion paste pulverized to a particle size of 8 μm. Next, pigment dispersion resin 349
g, 463 g of deionized water, 51% by mass of solid content, pigment mix char: pigment dispersion resin solid content = 1:
A final pigment dispersion paste of 0.25 mass ratio was obtained. (Preparation of electrodeposition paint) The same procedure as in Example 1 was carried out.

FIG. 1 shows the relationship between the dispersion time and the pigment particle size in the pigment paste dispersion step in each of the coating resin compositions obtained in Example 1 and Comparative Examples 1 and 2. As is clear from FIG. 1, in the coating resin composition of Example 1, the particle size of the pigment in the pigment dispersion paste was already 5 μm from 20 minutes after the start of the dispersion step, and the dispersion speed was high. In the coating resin composition of Comparative Example 1, the particle size of the pigment in the pigment of the pigment dispersion paste was 10 μm 20 minutes after the start of the dispersion step.
It was about 6 μm after 60 minutes. Further, in the resin composition for paint of Comparative Example 2, the particle size of the pigment in the pigment dispersion paste was as large as 8 μm at 20 minutes after the start of the dispersion step, and was about 5 to 6 μm after 60 minutes. Therefore,
Example 1 shows that the dispersion speed of the pigment is higher than that of Comparative Examples 1 and 2.

-Evaluation method- [Horizontal appearance (Method C, 5 minutes)] (1) Surfdyne SD5000 (Nippon Paint Co., Ltd.)
Cold rolled steel sheet (70 × 150 ×
0.8 mm). (2) 4 liters of the coating material are put in a square container made of polyvinyl chloride and stirred with a magnetic stirrer at a rotation speed of 600 rpm. (3) After setting the test plate of the above (1) in the coating liquid and reducing the rotational speed of the magnetic stirrer to 300 rpm,
Leave for a minute. (4) Stainless steel flat plate (70 × 1
(50 × 0.8 mm), and electrodeposition coating is performed at a rotation speed of 300 rpm so that the dry film thickness becomes 15 μm. (5) The coating is cured at 160 ° C. for 10 minutes, and the state of the coating film on the horizontal upper surface is evaluated according to the following criteria. Table 1 shows the evaluation results.

[0037]

[Table 1]

As shown in Table 1, a plurality of pigments were mixed, and the pigments of this mixed system were dispersed at an optimum mixing ratio with a resin and a solvent previously determined by the Daniel pour point method, pulverized and prepared by a sand mill. After obtaining the pigment dispersion paste,
The paint resin composition obtained by adding the other components (Example 1) is a paint resin composition not using the Daniel pour point method (Comparative Example 1), and each component is individually made of Danie.
The pour point was determined, and as compared with the coating resin composition (Comparative Example 2) obtained by proportionally distributing the composition of the pigment mixture, no occurrence of bumps was recognized and the result was good.

[0039]

As described above, according to the present invention, it is possible to improve the dispersibility of the pigment without changing the composition of the resin composition for coatings, thereby improving the productivity and the properties of the coating film. It is possible to provide a method for producing a resin composition for coatings that can be performed.

[Brief description of the drawings]

FIG. 1 is a graph showing a comparison between the dispersion speed of a pigment in Example 1 and Comparative Examples 1 and 2.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Koji Bessho 3-1-1-5 Nittacho, Takahama-shi, Aichi Japan Paint Co., Ltd. Aichi Works F-term (reference) 4J038 CG142 CH192 DB061 DB152 DB162 DB381 DG161 GA08 GA09 GA13 JA26 KA06 KA08 KA09 LA06 NA26 PA04

Claims (2)

[Claims] Claims: 1. A plurality of pigments constituting a coating resin composition are mixed, and the mixed pigment is dispersed at an optimum mixing ratio with a resin and a solvent previously determined by a Daniel pour point method, Thereafter, a method for producing a resin composition for a paint, which comprises adding a component for forming the resin composition for a paint. 2. The method for producing a coating resin composition according to claim 1, wherein the coating resin composition is an electrodeposition coating composition.